Learning Goals for Biology Programs
Understanding the unity and diversity of life requires mastery of a set of fundamental concepts. This understanding will be greatly enhanced if biology courses build on material begun in other science courses to expose students to the ideas of modeling and analyzing biological and other systems.
Biological systems show remarkable unity at the molecular and cellular levels, reflecting their common ancestry. Variations on this unity lead to the extraordinary diversity of individual organisms. In order for biology students to understand the unifying features of the biological concepts below, the concepts must be taught in multiple contexts. Biology faculty should consider the various points in their courses at which the concepts will fit. They should also consider the concept lists for chemistry, physics, and mathematics that will follow and the ways in which those ideas could be incorporated into biology courses. In order for biology students to receive a truly interdisciplinary education, cooperation between departments will be necessary. It is the responsibility of the biology faculty to make active outreach efforts to colleagues in other departments by offering to work together on mechanisms for incorporating biological concepts and examples into non-biology courses.
Concepts of Biology
- All living things have evolved from a common ancestor, through processes that include natural selection and genetic drift acting on heritable genetic variation.
- Biological systems obey the laws of chemistry and physics.
- Structural complexity and information content are built up by combining simpler subunits into multiple complex combinations.
- Understanding biological systems requires both reductionist and holistic thinking because novel properties emerge as simpler units assemble into more complex structures.
- Living systems are far from equilibrium. They utilize energy, largely derived from photosynthesis, which is stored in high-energy bonds or ionic concentration gradients. The release of this energy is couple to thermodynamically unfavorable reactions to drive biological processes.
- Although fundamental molecular and cellular processes are conserved, biological systems and organisms are extraordinarily divers. Unlike atoms and simple molecules studied in chemistry and physics, no two cells are identical.
- Biological systems maintain homeostasis by the action of complex regulatory systems. These are often networks of interconnecting partially redundant systems to make them stable to internal or external changes.
- Cells are fundamental units of living systems. Three fundamental cell types have evolved: bacteria, archea, and eukaryotes.
- Living organisms have behavior, which can be altered by experience in many species.
- Information encoded in DNA is organized into genes. These heritable units use RNA as informational intermediates to encode protein sequences, which become functional on folding into distinctive three-dimensional structures. In some situations, RNA itself has catalytic activity.
- Most biological processes are controlled by multiple proteins, which assemble into modular units to carry out and coordinate complex functions.
- Lipids assemble with proteins to form membranes, which surround cells to separate them from their environment. Membranes also form distinct compartments within eukaryotic cells.
- Communication network within and between cells, and between organisms, enable multicellular organisms to coordinate development and function.
- In multicellular organisms, cells divide and differentiate to form tissues, organs, and organ systems with distinct functions. These differences arise primarily from changes in gene expression.
- Many diseases arise from disruption of cellular communication and coordination by infection, mutation, chemical insult, or trauma.
- Groups of organisms exist as species, which include interbreeding populations sharing a gene pool.
- Populations of species interact with one another and the environment to form interdependent ecosystems with flow of energy and materials between multiple levels.
- Humans, as well as many other species, are members of multiple ecosystems. They have the capacity to disrupt or preserve the ecosystems upon which they depend.
- Excerpted from BIO2010: Transforming Undergraduate Education for Future Research Biologists, Committee on Undergraduate Biology Edcuation to Prepare Research Scientists for the 21st Century, National Research Council. 2003.